Anatomically modern humans
Anatomically modern human (AMH) refers to early individuals of Homo sapiens with an appearance fully congruent with that of modern humans. Anatomically modern humans evolved from archaic Homo sapiens in the Middle Paleolithic, about 200,000 years ago. The emergence of anatomically modern human marks the dawn of the subspecies Homo sapiens sapiens, i.e. the subspecies of Homo sapiens that includes all modern humans. The oldest fossil remains of anatomically modern humans are the Omo remains that date to 195,000 years ago. Other fossils include Homo sapiens idaltu from Herto in Ethiopia that are 150kya and remains from Skhul in Israel that are 90kya. Anatomy ]] Anatomically modern humans are distinguished from their immediate ancestors, archaic homo sapiens, by a number of anatomical features. Archaic homo sapiens had robust skeletons, indicating that they lived a physically demanding life; this may mean that anatomically modern humans, with their more gracile frames, had become more dependent on technology than on raw physical power to meet the challenges of their environment. Archaic homo sapiens also had very prominent brow ridges (protruding layers of bone above the eye socket). With the emergence of anatomically modern humans, the brow ridges had significantly reduced, and in modern humans they are, on average, barely visible. Another distinguishing feature of AMH is a prominent chin, something which is lacking in archaic homo sapiens. AMH also have a vertical forehead whereas their predecessors had foreheads that sloped backwards.Encarta, Human Evolution According to Desmond Morris, the vertical forehead in humans not only houses larger brains, but the prominent forehead plays an important role in human communication through eyebrow movements and forehead skin wrinkling. Early modern humans exhibiting a mix of archaic and modern traits.]] The Omo, Hertho, Skhul and Jebel Qafzeh remains are sometimes referred to as "Early Modern Humans" sometime as archaic humans because they skeletal remains exhibit a mix of archaic and modern traits. Skhul V for example, has prominent brow ridges and a projecting face. However the brain case of Skhul V is distinct from Skhul IX with the Neanderthals traits and are similar to the brain case of early modern humans. The above remains are dated indirectly. * directly dated early modern humans (EMH) 34 Elements of early modern humans were unearthed in 2003 in Tianyuan Cave, Zhoukoudian. 14C dated 42-39 ky Tianyuan 1 holotype are oldest, directly dated EMH bones in in eastern Eurasia. Tianyuan 1 exhibits series of typical modern, derived modern human features and few archaic traits. Late archaic human traits, such as a large hamulus length, anterior to posterior dental proportions and a broad and rounded distal phalangeal tuberosityhis morphological pattern imply multiregional evolution. Europe oldest EMH remains are from Peştera cu Oase near the Iron Gates in the Danubian corridor. Oase 1 holotype revealed specific traits combining a variety of archaic Homo, derived early modern humans]], and possibly Neanderthal features. Modern human attributes , placing it close to European early modern humans among Late Pleistocene samples. The fossil belongs to the few findings in Europe which could be directly dated and is considered the oldest known early modern human fossil from Europe. Two laboratories independently yielded collagen 14C of 40,500 years. Origins of modern humans There are two competing models that describe the origin of contemporary and recent humans. The mainstream view, known as the recent African origin model, holds that all existing human populations are descended from anatomically modern humans who lived in Africa 50-60kya. This model is supported by multiple and independent lines of evidence, such as the fossil record and genetics. The other theory known as the multiregional hypothesis, is held by a minority of scientists. According to the multiregional model, the various human populations around the world evolved from local archaic hominids such as homo erectus. The multiregional model posits that human populations achieved anatomical modernity independently, by convergent evolution. Modern human behavior There is considerable debate regarding whether the earliest anatomically modern humans behaved similarly to recent or existing humans. Modern human behaviors characteristic of recent humans include fully modern language, the capacity for abstract thought and the use of symbolism to express cultural creativity. There are two opposing hypothesis regarding the origins of modern behavior. Some scholars argue that humans achieved anatomical modernity first, around 200kya, and only later did they adopt modern behaviors around 50kya. This hypothesis is based on the limited record of fossils from periods before 50kya and the abundance of human artifacts found after 50kya. Proponents of this view distinguish anatomically modern humans from behaviorally modern humans.